95% of the bodys fatEnerg source when plasma glucose is decreasedT. catabolism is regulated by lipase, epinephrine and cortisol.Transported by chylomicrons and VLDL

Cholesterol

Found only in AnimalsImportant component of membrane, steroid hormones, bile and Vit. D.Dietary sourcesynthesized by the liver

Cholesterol

70% is associated with cellular components30% is in the plasma (1/3 free form, 2/3 esterfied)Transported by HDL and LDL

Phospholipids

Important components of cell membranesLecithin and sphingomyelin are utilized to determing fetal lung maturity and amniotic fluid (L/S ratio)

Glycolipids

Lipids with a carbohydrate componentABO antigens are glycolipids

Apoliproproteins

*Outer protein shell of lipoprotein*The lipid protein interactions allows the water insoluble lipid to become soluble in plasma.*Responsible for the interactions with cell membranes and enzymes to transport lipids to specific locations.

HDL composition

30% Phospholipids20% Cholesterol50% Apoprotein

What major protein found in HDL?

Apo - A1 HDL

What Apolipoprotein is associated with high risk of CVD?

Apo - B LDL

What Apolipoprotein is associated with chylomicron remnants and renal failure?

Apo - C

Activates lipoprotein lipase?

Apo - C2

The exogenous pathway involves primarily which lipoprotein?

Chylomicrons

Chylomicron emnants are catabolized and channeled in what three pathways?

Synthesized VLDL, Released to form bile acids, Stored as cholesterol ester.

Lipoprotein physiology and metabolism

*Water insoluble lipids are digested into more water soluble.*Triglycerides are digested into fatty acids.*Cholesterol esters are converted into free cholesterol*Fatty acids are converted into triglycerides by the liver and adipose tissue.

Lipoprotein physiology and metabolism

Most cholesterol synthesis occurs int the liver.Most cholesterol lowerin drugs target this synthesis.Cholesterol is a main component of bile (needed for dietary absorption of fat)

Exogenous Pathway

Transport of dietary lipids, mostly tge chylomicrons transportation of triglycerides to the liver.

Endogenous Pathway

Transportation of lipids from the liver to the tissues VLDL and LDL

Effects of Hormones (Insulin)

Decreases plasma glucoseInactivates lipase which dec lipolysis and the catabolism of trigs to fatty acids/ glucose.Stimulates lipogenesis (FA to Trigs)Helps make fat